GHAFOURI ET AL.
5 of 6
The liberated hydrogen converts the produced styrene
4 | CONCLUSION
to ethyl benzene. On the other hand, the styrene oxide
acts as hydrogen acceptor and is converted to 1–phenyl
ethanol.[35] Therefore, in all reactions, small amounts of
ethyl benzene, 1–phenyl ethanol and the corresponding
aldehyde were also detected.
Comparison of the catalytic activity of these two cata-
lysts shows that the [Ru–H@AuNPs–TD] is more reactive
than [Ru–H@EDT–MWCNT] in the direct oxidation of
alcohols to carboxylic acids with styrene oxide. This can
be attributed to the smaller size of the gold nanoparticles
compared to MWCNTs.[37,38]
In conclusion, two heterogeneous catalysts based on the
supporting of ruthenium hydride catalyst supported on
multi‐walls carbon nanotubes and gold nanoparticles
cored triazine dendrimer were applied for direct oxidation
of alcohols to carboxylic acids with styrene oxide via
transfer hydrogenation. The prepared catalysts were high
stability and reusability in oxidation of alcohols.
ORCID
On the other hand, these two catalysts are more effi-
cient that homogeneous counterpart. The TOFs for homo-
geneous catalyst are about 1.33–1.55 h−1, while in the
presence of both these catalysts the TOFs reached to
6.42–11.5 h−1. This may be due to the dispersion of cata-
lytic active site on high surface are nanoparticles which
increases the accessibility of active sites for the substrates.
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FIGURE 2 Catalyst recovery and reuse in the oxidation of benzyl
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